The present invention relates to the technical field of instrumentation covering all fields of activity and serving to provide access or illumination, or to examine the inside of a body in the general sense, such as a cavity or a channel.
More precisely, but not exclusively, the present invention relates to an instrument for a medical endoscope for single use or multiple use, serving to illuminate and to examine the inside surface of a hollow organ, cavity, or natural or artificial duct in the human body for therapeutic, surgical, or diagnostic purposes.
The instrument of the invention is used for diagnostic or surgical purposes to inspect any internal portion of the human body that can be accessed via natural or artificial paths. For example, the endoscope instrument of the invention may be used in the field of urinary tract, gastrointestinal tract, the respiratory system, the cardiovascular system, the trachea, the sinus cavity, the reproductive system in women, the abdominal cavity, or any other portion of the human body for investigating via a natural or an artificial path.
In the above technical field, various types of endoscope exist that are adapted to organs that are accessible for observing. In general, an endoscope comprises a more or less flexible insertion tube possessing a proximal portion for connection to an actuation support that enables the tube to be steered inside the insertion path. The endoscope also includes a display system, generally an optical display system, that serves to illuminate and to examine the organ, the cavity, or the duct of the human body from the distal portion of the insertion tube. In numerous applications, it is found to be advantageous to bring one or more appliances to the distal portion of the insertion tube, in association with the access, lighting, and observation zone, the appliance(s) being adapted to enable various functions to be performed such as: delivering fluid; delivering instruments; taking samples; or performing surgical operations. The distal portion of the insertion tube thus presents an outlet section that is occupied in part by the lighting and observation zone, and in part by the orifice for passing one or more appliances.
It should be considered that the outlet section of the distal portion of the insertion tube presents a magnitude that is limited by the smallest width of the natural or artificial access path in which the insertion tube is engaged.
Even though the miniaturization of appliances is continuously making advances, the development of ever more complex appliances requires a relatively large section for passing the appliance in the distal portion of the insertion tube. In analogous manner, the need to obtain an image of good quality requires a lighting and observation zone of sufficient area to be available at the distal portion of the insertion tube.
In an attempt to remedy those opposing constraints, international patent application WO 2005/104927 proposes an endoscope having an insertion tube in which the distal portion is fitted with hinge means that enable tooling and/or the optical observation system to be deployed radially. It should be observed that that technical solution can be implemented only in the context of a hollow organ of section that is greater than the section of the endoscope access path. It should be considered that the operation of hinge means requires a relatively large deployment zone to be available, thereby limiting the use of that endoscope. In addition, radial deployment of the hinge means might damage the tissue of the inspected organ. Furthermore, the hinge means are found to move in random manner and to be difficult to control. Finally, the distal portion of the insertion tube is found to be difficult to decontaminate thoroughly.
For the same purpose, U.S. Pat. No. 5,025,778 describes an endoscope having an insertion tube with deformable tubing engaged on its outside over its entire length, the tubing being arranged in an expanded position to define at least one passage channel. Before the endoscope is inserted in the patient, the channel is not formed such that the deformable tubing is pressed against the insertion tube. After the endoscope has been inserted in the patient, a fluid or a tubular element is moved along the passage channel in order to put it into its expanded position.
In similar manner, U.S. Pat. No. 5,503,616 describes an endoscope having an insertion tube with a deformable membrane fitted to the outside thereof over its entire length, the membrane being arranged, when in an expanded position, to define a channel for passing equipment.
Those technical solutions increase the section of the endoscope for passing an appliance by adding tubing or a deformable membrane to the insertion tube, the tubing or the membrane then not being configured in its expanded position. The extra thickness fitted on the insertion tube makes it necessary, for a given through section in the access path, to reduce the size of the insertion tube and consequently to limit or reduce the size of the appliances and/or the viewing system.
Furthermore, those technical solutions give rise to an increase in the through section of the endoscope over the entire length of the insertion tube, and sometimes that is not possible or at the least runs the risk of discomforting the patient or damaging tissue around the access path.
The present invention thus seeks to remedy the above-specified drawbacks by proposing an endoscope instrument in the general sense, and more particularly for use in the medical field, the instrument presenting a miniaturized distal portion providing good quality observation and the possibility of bringing various appliances to said distal portion while avoiding damage to the surrounding organs or tissue.
Another object of the invention is to provide an endoscope instrument in which the insertion tube does not present extra thickness and that is suitable for optimizing use of the space available in the access path in the patient through which the endoscope passes.
To achieve this object, the endoscope instrument comprises an insertion tube of longitudinal axis possessing a proximal portion for connection to an actuation support and a distal portion presenting an outlet section occupied in particular firstly by a viewing zone and secondly by at least one outlet orifice for passing at least one appliance for occupying a retracted position inside the tube and a working position in which the appliance occupies at least a portion of the outlet section. According to the invention, the distal portion of the insertion tube includes at least one radially deformable wall over a portion of its length extending from the outlet section, thereby enabling the outlet section of the distal portion of the tube to be increased on the appliance passing from its retracted position in which the appliance does not stress the deformable wall to its working position in which the deformable wall is stressed radially, the outlet section of the distal portion corresponding to the right cross-section of the insertion tube in the retracted position of the appliance.
According to an advantageous embodiment characteristic, the distal portion of the insertion tube is provided with a sealing member closing the outlet orifice of the passage for the appliance. This sealing member serves to avoid contaminating the appliance throughout the insertion movement of the insertion tube, or to keep the appliance sterile.
For example, the sealing member is a plug that is ejectable or a membrane that is tearable by the appliance or by fluid pressure.
In another embodiment, the appliance comprises at least one tubular duct mounted inside the insertion tube so as to be slidable relative to the insertion tube.
The appliance includes at least one tool optionally mounted in the tubular duct.
In another variant, the distal portion of the tubular duct is provided with at least one sealing envelope.
For example, the sealing envelope presents mechanical strength that is greater than that of the sealing member carried by the distal portion of the insertion tube.
In another example, the sealing envelope of the tubular duct is an envelope that is tearable by the tooling housing inside the tubular duct.
According to an embodiment characteristic, the insertion tube includes, in its distal portion, a guide system for guiding the appliance in order to enable the deformable wall to be expanded radially during the movement of the appliance.
In an embodiment, the distal portion of the insertion tube is embedded in a deformable material internally defining the passage for the appliance.
In a preferred embodiment, the distal portion of the insertion tube includes a viewing system.
It should be observed that the distal portion or head of the instrument is optionally removable relative to the insertion tube.
For example, the viewing system is embedded in the deformable material.
The invention also proposes an endoscope provided with an instrument in accordance with the invention.
Various other characteristics appear from the following description with reference to the accompanying drawings that show embodiments of the invention as non-limiting examples.